1. Field
Exemplary embodiments of the present disclosure relate to a screw shaft support and a twin screw extruder machine (TSM) comprising the same.
2. Discussion of the Background
The manufacture of ceramic honeycomb structures may be accomplished by the process of plasticizing ceramic powder batch mixtures, extruding the mixtures through honeycomb extrusion dies to form honeycomb extrudate, and drying and firing the extrudate to produce ceramic honeycombs of high strength and thermal durability. The ceramic honeycombs thus produced are widely used as ceramic catalyst supports in motor vehicle exhaust systems, and as catalyst supports and wall-flow particulate filters for the removal of soot and other particulates from diesel engine exhausts.
Among the commercially successful processes for ceramic honeycomb manufacture are those that utilize large co-rotating twin screw extruders for the mixing and extruding of ceramic honeycomb extrudate. These machines offer the capability of homogenizing and plasticizing ceramic powder batch mixtures and pressure-forcing the mixtures through honeycomb extrusion dies, such as in a single continuous processing operation. The favorable economics of this approach extend from the high-volume production of honeycombs of relatively small diameter for automobile exhaust systems to the shaping of very large frontal area (VLFA) honeycombs for large diesel engine exhaust systems. Cylindrical honeycomb shapes having cross-sectional diameters measured transversely to the cylinder axis and direction of honeycomb channel orientation can range from as small as 5 cm up to 50 cm or more.
The rotating screws used in extruders commonly comprise a plurality of screw segments that are successively positioned, such as on a splined or keyed axial drive shaft, to form the entire screw. Screw segments may be made of any suitable material, such as metal or ceramic.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the claimed invention and therefore it may contain information that does not form any part of the prior art nor what the prior art may suggest to a person of ordinary skill in the art.